Pure cotton shorts are cheaper than recycled fiber shorts because of different fabrics, and pure cotton shorts are cheaper. The fiber recovered from cellulose is called regenerated cellulose fiber. Underwear generally uses pure cotton, modal and bamboo charcoal fibers. Modal and bamboo charcoal fiber are regenerated cellulose fibers, each with its own advantages. Underwear made of pure cotton fabric will have better sweat absorption, but it is not suitable for people who are prone to sweating, because good sweat absorption will often give our genitals a moist state. Modal is characterized by softness, moisture absorption and good air permeability, but modal underwear is relatively expensive.